Abstract

Among all the type of inorganic compounds now developed, 36% of structures based on borate are non- centrosymetric while only 15 % of the all reported inorganic structures are non-centrosymetric. Consequently, all the recent NLO material discovered, in the last 5 years, are in majority borate based crystals. The calcium rare earth oxoborate family Ca4ReO(B03)3 (Re=Gd, Y) are among these recent NLO crystals with a very promising future. This family was first studied with the now well known Ca₄GdO(BO₃)₃ compound named GdCOB. The GdCOB was shown to be an efficient nonlinear optical crystal [1] grown from the melt in large size. The effective NLO coefficient is about 1pm/V. it damage threshold is up to 1Gw/cm2 at 1064 nm (6 ns pulses). The ReCOB family offers a unique opportunity to study the structure-properties relations because of it wide variety of composition. It is possible in this oxoborate family for example to tune the composition in order to get good NLO properties for particular wavelength frequency conversion.

© 2000 IEEE